Placeholder feature to sketch out what we want
Add model for the take part pages on the get involved section

NOTE: In light of https://www.pivotaltracker.com/story/show/46723655 (warn about db field limits) we're validating the size of the body field, which is backed by a MySQL MEDIUMTEXT (~ 16 Megabytes).  Rails default length (for rails < 3.2) validator tokenizes the string which takes ages on large values.  We specify a default tokenizer that simply returns the value (the validation really relies on the length method being present).
Add ordering to take part pages

We force pages to the bottom of the list when created if an ordering hasn't been specified.
CRUD and admin nav for take part pages

I've added them as a tabbed section to a new "get involved" section on the admin, currently this is just for the take part pages, but I think there is more to come.  If that's not the case I'll remove this page, as it's a bit weird.
Allow deleting too (via a button on the edit page?)

Putting it there seems weird, but there's no where else for it to go that makes sense.
Add TakePartPage.reorder! and controller action for it

Takes a list of take part page ids and reorders them in the list order.  Will put anything *not* in the list at the end.
Use an array for next_closing_consultations on home#get_involved

For some reason a single consultation in a presenter doesn't work properly when the consultation is nil, but it does work properly when the array is empty.
Display take part pages on frontend
Flesh out steps for take part pages feature
Add navigation highlight to get involved for take_part_pages_controller
Add permissions for admin get involved section: only gds editors
Fix up authority tests so they can run on their own again
Clarify step about reordering pages
Add live edits warning and govspeak helper to take part pages form